支座约束及荷载分布对薄壁深梁应力的影响  

THE EFFECT OF SUPPORT RESTRAINT AND LOAD DISTRIBUTION ON STRESS OF THIN-WALLED DEEP BEAMS

作　　者：刘计良[1,2] 张学森[1] 王正中[1] 韩彦宝[1] 

机构地区：[1]西北农林科技大学水利水电工程研究所,陕西杨凌712100 [2]西北农林科技大学理学院,陕西杨凌712100

出　　处：《工程力学》2011年第8期23-29,共7页Engineering Mechanics

基　　金：国家"863"计划项目(2002AA62Z3191);陕西省自然科学基金项目(97C19)

摘　　要：薄壁深梁的应力精确计算是个复杂的力学问题。该文在以往研究工作的基础上,运用弹性力学中的半逆解法并考虑了弯剪耦合效应,引入合理的无量纲参数,推导出不同支座约束及不同荷载分布作用下工字形截面深梁的应力计算公式。通过对无量纲翘曲正应力的分析指出:支座约束越强,翘曲正应力越大;线性分布荷载变化率越大,翘曲正应力越大。薄壁深梁的弯应力数值总大于用材料力学中细长梁纯弯曲理论计算出的弯应力的值,对这类梁的强度验算及设计应考虑附加的翘曲正应力。The Accurate calculation of stress for thin-walled deep beams is a complex mechanical problem. Based on the previous studies, formulas for computing stresses of deep beams with I section subjected to different support restraints and load distributions are obtained by using the semi-inverse method in elastic mechanics and reasonable dimensionless parameters, and bending-shearing coupling is also considered. The analysis of dimensionless warping normal stress indicates as follows： a stronger support restraint leads to larger warping normal stress; the larger change rate of a linear load leads to larger warping normal stress. The values of normal stresses of thin-walled deep beams are always larger than those obtained by pure bending theory of slender beams in material mechanics. This will cause unsafe engineering design. Therefore, the warping stress should be considered in the design and strength＇checking for deep beams.

关 键 词：薄壁深梁 翘曲应力 半逆解法 弯剪耦合 工字形截面 支座约束 荷载分布 

分 类 号：TB125[理学—工程力学] TV332.4[理学—力学]